package com.yyl.common.util;

import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.servlet.http.HttpServletRequest;
import java.util.Objects;

@Component
public class SpringContextUtils implements ApplicationContextAware {

    /**
     * 上下文对象实例
     */
    private static ApplicationContext applicationContext;

    /**
     *  设置程序上下文
     * @param applicationContext
     * @throws BeansException
     */
    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        SpringContextUtils.applicationContext=applicationContext;
    }

    /**
     * 获取 applicationContext
     * @return
     */
    public static ApplicationContext getApplicationContext(){
        return applicationContext;
    }

    /**
     *  获取 HttpServletRequest
     * @return
     */
    public  static HttpServletRequest getHttpServletRequest(){
        return ((ServletRequestAttributes) Objects.requireNonNull(RequestContextHolder.getRequestAttributes())).getRequest();
    }

    public static String getDomain(){
        HttpServletRequest request=getHttpServletRequest();
        StringBuffer url=request.getRequestURL();
        return url.delete(url.length() - request.getRequestURI().length(), url.length()).toString();
    }

    public static String getOrigin(){
        HttpServletRequest request=getHttpServletRequest();
        return request.getHeader("Origin");
    }

    /**
     * 通过 name 获取 Bean
     * @param name
     * @return
     */
    public static Object getBean(String name){
        return getApplicationContext().getBean(name);
    }

    /**
     *  通过class 获取 bean
     * @param clazz
     * @param <T>
     * @return
     */
    public static <T> T getBean(Class<T> clazz){
        return getApplicationContext().getBean(clazz);
    }

    /**
     *  通过 name。已经Class 返回指定的Bean
     * @param name
     * @param clazz
     * @param <T>
     * @return
     */
    public static <T> T getBean(String name,Class<T> clazz){
        return getApplicationContext().getBean(name,clazz);
    }



}
